Subwoofer Set Up

My room is 17L x 12W x 8.7H. I was thinking to go with 2 channel set up. Monitors plus 12" Sub. Should I go with two
10" Subwoofers and what is the best Sub position. So far the
best bass response comes from front right corner. Thanks
It's doubtful that a 10" driver can deliver clean bass, but it depends on your room and needs. I'd choose a 12" driver in the biggest box you can afford and tolerate. For a music only system, a sealed box may be better than ported. In general, two subs can yield a smoother response across a larger area than a single sub assuming no restriction on location. The best location for a sub is room dependent. You might want to read the Harman paper on multiple subs: Click on White Papers and then "Subwoofers: Optimum Number and Locations", as well as, "Part Three: Getting the Bass Right ".
Bob and I totally disagree on this, he comes from a HT perspective while I am oriented toward audio. There are several subs that will work, I use REL and Hsu. The larger subs will overpower your room, I have a pair that use 4 12" a side in a large cabinet and I don't use them in my room which is similar to yours except being twice as long. Two 10" subs will give you all the bass you need in a room your size. Or one 10" or 12" if they are good quality. I would start with one better one and add a second later rather than start with 2 cheaper ones if that was the choice. There are several other powered subs that I have not used that have good reputations.
First, I don't come from an HT nor music perspective, because to achieve good sound the requirements are the same. Second, I don't how a 35 Hz frequency produced by a 12" driver can "overpower" your room any more than if it were produced by a 10" driver. As long as you can match the level between the sub(s) and the main speakers, you'll be fine.

I do agree with Stanwal's logic: "start with one better one and add a second later rather than start with 2 cheaper ones".
Bob and Stanwal, Thanks for response. I was thinking to go
with one REL B2, 10" and then to add another if necessary or I
should go with one B1, 12". I would really appreciate Yours
Two subs from the start. Check out Floyd Toole's comments on this area, in his book 'Sound Reproduction'
I stand by my comment that I would choose a 12" driver over a 10" driver. The size of the cabinet will have a big impact on the performance of the sub. So it's possible that a smaller box 12" sub will equal the performance of a larger box 10" sub.

Before picking a sub, I suggest you consider the possibility of using a bass equalizer and depending on your main speakers and electronics an external bass management controller. In other words, look at the whole system not just the sub.

Finally, I suggest you take a look at SVS subs and their equalizer.
Check out the research on sub placement by Welti, Toole et all at Harman International. With two subs, try placing them at the mid points of each side wall as a starter. Also read Dr Floyd Toole's lastest book where he spends many pages considering placement for constructive and deconstructive interferance to help reduce peaks and raise nulls.